org.hibernate.util

Class CollectionHelper

java.lang.Object

org.hibernate.util.CollectionHelper

public final class CollectionHelper
extends java.lang.Object

Various help for handling collections.

Author:

Gavin King, Steve Ebersole

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.Collection	EMPTY_COLLECTION
static java.util.List	EMPTY_LIST
static java.util.Map	EMPTY_MAP
static float	LOAD_FACTOR
static int	MINIMUM_INITIAL_CAPACITY

Method Summary

Methods

Modifier and Type	Method and Description
static <T> java.util.List<T>	arrayList(int anticipatedSize)
static int	determineProperSizing(int numberOfElements) Determine the proper initial size for a new collection in order for it to hold the given a number of elements.
static int	determineProperSizing(java.util.Map original) Given a map, determine the proper initial size for a new Map to hold the same number of values.
static int	determineProperSizing(java.util.Set original) Given a set, determine the proper initial size for a new set to hold the same number of values.
static java.util.Map	mapOfSize(int size) Build a properly sized map, especially handling load size and load factor to prevent immediate resizing.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MINIMUM_INITIAL_CAPACITY

public static final int MINIMUM_INITIAL_CAPACITY

See Also:

Constant Field Values

LOAD_FACTOR

public static final float LOAD_FACTOR

See Also:

Constant Field Values

EMPTY_LIST

public static final java.util.List EMPTY_LIST

EMPTY_COLLECTION

public static final java.util.Collection EMPTY_COLLECTION

EMPTY_MAP

public static final java.util.Map EMPTY_MAP

Method Detail

mapOfSize

public static java.util.Map mapOfSize(int size)

Build a properly sized map, especially handling load size and load factor to prevent immediate resizing.

Especially helpful for copy map contents.

Parameters:

size - The size to make the map.

Returns:

The sized map.

determineProperSizing

public static int determineProperSizing(java.util.Map original)

Given a map, determine the proper initial size for a new Map to hold the same number of values. Specifically we want to account for load size and load factor to prevent immediate resizing.

Parameters:

original - The original map

Returns:

The proper size.

determineProperSizing

public static int determineProperSizing(java.util.Set original)

Given a set, determine the proper initial size for a new set to hold the same number of values. Specifically we want to account for load size and load factor to prevent immediate resizing.

Parameters:

original - The original set

Returns:

The proper size.

determineProperSizing

public static int determineProperSizing(int numberOfElements)

Determine the proper initial size for a new collection in order for it to hold the given a number of elements. Specifically we want to account for load size and load factor to prevent immediate resizing.

Parameters:

numberOfElements - The number of elements to be stored.

Returns:

The proper size.

arrayList

public static <T> java.util.List<T> arrayList(int anticipatedSize)